Engine starter



July 21, 1931. H. BURTON 1,815,047

ENGINE STARTER Filed Oct; 1, 1928 INVE'NT 0R.

patented July 21,

UNITED STATES HENRY BURTON, F GARD ENA, CALIFORNIA ENGINE srnnr'nnApplication filed October 1, 1928, Serial No. 309,572.

My invention relates to a well known type of engine starter, in which anormally idle drivingpinion is shifted endwise into mesh with a gearattachedto the engine,

by the action. of the starting motor. Usually the driving shaft isprovided with screw threads and the pinion acts as a nut threadedthereon, or the pinion is provided with an extension sleeve havinghelical slots in which operateradial projections of the shaft. In anycase the shifting of the pinion into and out of mesh with the drivengear is contingent upon a slippage or relative rotation between thepinion and the driving element The general characteristics of a starterrepresentative of this type is fully disclosed in Patent No. 1,095,696,May 5th, 1914, Joseph Bijur.

Starters of the type referredto, are also in general use on automobilesand are well known to persons skilled in the art, therefore it is deemedunnecessary to encumber this specification with illustrations anddescriptions of the accessory elements, such as source of power, meansfor connecting and controlling-the same and the'manner of-supportingthestarter relative to the engine with which it operates.

As-usual ly constructed, starters of the type referred to possess twoparticular disadvantages one of which is the very abrupt start of themotor. necessary to turn the driving element relative to the pinion,which is usually held from simultaneous rotation therewith only by itsinertia. This abrupt start results in the gears meshing withsevereshockdisagreeable from an operating standpoint and the cause of'excessivewear and tear, materially shortening driven gear so as to insure themeshing of same. The teeth of the pinion often clash with the teeth ofthe engine gear, the result being chipped and broken gear teeth andoften a complete lock of the mechanism.

The object of my invention, is, first, to provide a simple and positivemeans that will hold the pinion against rotation in its idle positionand until after it has shifted into engagement with the driven gear, yetwill offer no impediment to the free rotation on its return movement;and, second, to provide simple and positive means to so position theteeth of the pinion with reference to the teeth of thedrivengear thatthey will i enter into mesh easily and-without clashing.

In describing the invention, reference is had to the accompanyingdrawings, in which:

Fig. 1 is a half section of the starter mounted onthe extended armatureshaft of the starting motor, showing also a part of the engine gear andits position relative to the starter. v

Fig. 2 is a rear end elevation. of the starter removed from the armatureshaft.

Fig. 3 shows an alternative construction of the means for turning thepinion 'toa position requisite for entering its teeth into mesh with theteeth of the driven gear.'

Fig. 4 illustrates an alternative construc tion of the brake or lockingdevice.

Referring to Fig. 1, the screw threaded sleeve 1 fits freely upon thedriving shaft 2 and is yieldingly held thereon by the coil spring 4, oneend of which is secured to the driving shaft by the set screw5 threadedthrough the collar 6, the opposite end being anchored to the end of thesleeve 1 by the cap screw 7.

The driving pinion 8 is threaded on sleeve 1 and is free to rotate andtravel longitudinally thereon within the limits of the threaded portionthereof.-

On the back of pinion 8 is formed or attached a flange carrying thecurved spring leaf 9, on the free end ofwhich is the weight 10 and thebrakemember 11 (see Figs. 2 and 4). I

The member 11 normally engages the ring 12 stationary and concentricwith reference loosely fitted the pin 13. Pin 13 is slightly longer thanthe thickness of the wall of the sleeve 1, is rounded on the inner endand projects through the wall of the sleeve into the V-shaped notch 14in the driving shaft. The pinion 8 is somewhat longer than itslongitudinal travel so that it will at all times cover the pin 13' andwill retain it in place in the wall of the sleeve.

The action of the device is as follows. When the shaft 2 is rotated, thesleeve 1 rotates with it. The pinion 8 is held from rotation by thebrake member 11 in contact with the stationary brake member or ring 12.The pinion is screwed forward along the threads of the sleeve, drawingthe brake member longitudinally along the ring 12.

Before the brake member 11 has traveled out of contact with the ring l2the pinion teeth will have engaged the engine gear 15 and the pinionwill continue to move longitudinally until stopped by the collar 16,when no further longitudinal motion being possible, the pinion mustrevolve with sleeve 1 and start the engine.

The brake members will now be out of contact and will offer noresistance to rotation of the pinion.

When the engine starts on its own power, the pinion 8 is driven at aspeed greater than that of sleeve 1 and is screwed back to its startingpoint. Now, however, the pinion is revolving and the weight 10 by reasonof the centrifugal force draws the member 11 out of contact with thering 12 and also causes the pinion to bind on the sleeve so that itcontinues to revolve with it and will not again travel toward the enginegear.

When the shaft 2 and sleeve 1 come to rest, the pinion of course stopsand the spring 9 presses the member 11 into engagement with the ring 12and holds the pinion from creeping on the sleeve as it would tend to doby reason of vibration of the engine or car to which it is attached.

The above sequence of actions presupposes that the teeth of the pinionand engine gear are so positioned relative to each other that they willenter into mesh without opposition. In the event that the teeth of thepin ion and gear meet in opposition, the forward longitudinal motion ofthe pinion 8 is of course arrested.

Continued rotation of the sleeve 1 screws it backward out of the pinionagainst the resilience of the spring 4 until the pin 13 rides upon theinclined side of the notch 14 and it wedged out against the innersurface ofthe pinion 8, clamping it tight on the sleeve 1, so that nomore forward thrust is applied and no greater pressure can be exertedagainst the ends of the teeth than is requiredto compress the spring 4.

The continued rotation of the driving shaft rotates the pinion so thatits teeth move past the teeth of gear l5. As they come opposite thespaces between the teeth of gear 15, opposition to the forward movementof the pinion is removed, spring 4: expands and pushes the sleeve 1,together with the pinion forward meshing the gears.

The pin 13 slides into notch lel, releases the pinion onthe sleeve 1 andthe normal operation proceeds as hereinbefore described.

The operation of the structure shown in Fig. 3 is similar. In thisconstruction the P1101317 has teeth of the same ,form and pitch as thepinion 8. It is supported slightly in advance of the face of the pinionand is held in a plane vertical to the axis of the shaft by the coilspring 20 and the studs 19. The holes through which the studs 19 passare somewhat larger than the studs and the bore of the pilot fits theshaft loosely.

I Normally the pilot 17 acts as an integral part of the pinion 8. Ifwhen ninion 8 approaches the gear 15 it is so positioned that its teethare in opposition to the teeth of the gear, the teeth of the pilot willmeet the gear teeth end on and the pilot will be .canted (as shown indotted lines) so as to bind on the shaft 2 and the effect will be tocause pinion 8 to turn with the shaft until the teeth are out ofopposition when the spring 20 will straighten up the pilot as its teethenter into mesh with the gear 15; otherwise the operation is ashereinbefore described.

'Referring to the modified construction illustrated in Fig. 4, the ring12 is provided with teeth and the-member 11- is simply the end of thespring 9 formed so as to engage the said teeth. In this constructioncare is used toadjust the spring 9 and shape the teeth of the ring 12 sothat the resistance to rotation of the pinion may be overcome by thefull torque of the motor, as the meshing of the gears sometimes requiresa slight turn of the pinion before the brake is released. The specificmeans by which the pinion is shifted is immaterial to the inventionintended to be herein described. However, the shifting means illustratedin Fig. 3 may be, and sometimes is, used and for simplicity ofconstruction it may be preferable to use the gear meshing means thereillustrated with that form of shifting means, inasmuch as the sleeve 1and spring a may be omitted. It will be understood that minor changesinthe size, form and construction of the various parts of my improvedengine starter maybe made and substituted for those herein shown anddescribed without departing from the spirit of my invention, the scopeof which is set forth in the appended claims.

I claim as my invention:

1. The combination in an engine starter of the character described, of adriving shaft, a driving member adapted to shift longitudinally of saiddriving shaft into and out of engagement with, a driven member; alocking means adapted to oppose rotation of the driving member, whensaid. driving member is at rest in normal position and means, responsivetothe centrifugal force of rotation of the driving members adapted torender the locking means inoperative during operation of the startersubsequent to engagement of the driving and driven members.

2. The combination in an engine starter of the character described, of adriving shaft, a driving member adapted to shift longitudinally of saiddriving shaft into and out of engagement with a driven member; astationary locking element, a locking element associated with thedriving member, normally cooperating with said stationary lookingelement, means responsive to the centrifugal force of rotation of thedriving members, adapted to prevent cooperation of said locking elementsduring operation of the starter subsequent to engagement of the drivingand driven members.

3. The combination in an engine starter of the character described, of adriving shaft, a driving member adapted to shift longitudinally of saiddriving shaft into and out of engagement with a driven member; a lockingelement, flexibly attached to the driving member, a stationary lockingelement, a resilient element, adapted to normally cause cooperation ofthe locking elements and a weight associated with the first namedlocking element, revolvable with the driving members responsive tocentrifugal force of said rotation, adapted to move and to hold saidlocking elements out of cooperative relation, as an incident of therotation of the driving members during operation of the starter.

45. An engine starter of the character de scribed comprising incombination a motor, a driving shaft operated thereby, a screwthreadedsleeve, rotatable therewith and movable axially thereof a springconnecting the screw threaded sleeve and driving shaft, an internallythreaded pinion adapted to travel longitudinally of said sleeve, intoand out of engagement with a driven gear, a

clamping element associated with the screwthreaded sleeve, movablerelative thereto, and means associated with the driving shaft whereby aslight axial movement of the sleeve relative to the shaft actuates theclamping element into clamping cooperation With the pinion.

5. An engine starter of the character described, comprislng 1nCOI'XlblIlELtlOIl a motor,

a driving shaft, operated thereby, a screwthreaded sleeve, rotatabletherewith and movable axially thereof a spring connecting the screwthreaded sleeve and driving shaft, an internally threaded pinion adaptedto travel longitudinally of said sleeve into and out of engagement witha driven gear, a clamping member in the wall of the screwthreadedsleeve, movable radially thereof and means associated with the drivingshaft whereby a slight axial movement of the sleeve relative to theshaft serves to actuate the clamping element radially into clampingcooperation with the driving pinion.

6. An engine starter comprising in combination, a notched driving shaft,a sleeve,

movable axially thereof, a spring connecting the sleeve and drivingshaft, a driving pinion adapted to shift axially of said sleeve anddriving shaft, into and out of engagement with a driven gear andclamping means, associated with the sleeve, coacting with a notch in thedriving shaft to clamp the driving pinion to the driving shaft at anintermediate stage of its axial travel thereof, incident to relativeaxial movement between the sleeve and driving shaft, whenever the teethof said driving pinion abut against the teeth of the driven gear.

In testimony whereof I affix my signature.

HENRY BURTON.

